Controlling refreshes of pixels in display devices

Abstract

A display device includes pixels, a serial-to-parallel converter (SPC), a row driver, a column driver, and a switch. The pixels are arranged in rows and columns which include a first column and a first row. A first pixel resides at an intersection of the first row and first column. The SPC extracts, from a signal sent by a graphics controller, pixel data and a command. The row driver initiates a refresh of the pixels residing in the first row based on the pixel data. The column driver transmits the pixel data to the first column. During the refresh, the switch allows transmission of the pixel data to the first pixel when the command indicates that the first pixel is to be refreshed and prevents transmission of pixel data to the first pixel when the command indicates that the first pixel is not to be refreshed.

What is claimed is: 
     
       1. A display device, comprising:
 a plurality of pixels arranged in a plurality of rows and a plurality of columns, wherein the plurality of columns includes at least a first column, the plurality of rows includes at least a first row, and the plurality of pixels includes at least a first pixel residing at an intersection of the first row and the first column; 
 a serial-to-parallel converter to extract pixel data from a first field of a data packet sent by a graphics controller and to extract a command from a second field of the data packet indicating whether the first pixel is to be refreshed; 
 a row driver coupled to the first row to initiate a refresh of those pixels of the plurality of pixels residing in the first row based on the pixel data; 
 a column driver coupled between the serial-to-parallel converter and the first column to transmit the pixel data to the first column; and 
 a switch coupled to the column driver to allow transmission of the pixel data to the first pixel during the refresh when the command indicates that the first pixel is to be refreshed and to prevent transmission of the pixel data to the first pixel during the refresh when the command indicates that the first pixel is not to be refreshed. 
 
     
     
       2. The display device of  claim 1 , wherein the display device is a head mounted display. 
     
     
       3. The display device of  claim 1 , wherein the display device is a touchscreen device in communication with an active stylus. 
     
     
       4. The display device of  claim 1 , wherein the switch closes to allow transmission of the pixel data to the first pixel and opens to prevent transmission of the pixel data to the first pixel. 
     
     
       5. The display device of  claim 4 , wherein opening of the switch causes the first column to be held in a tristate mode. 
     
     
       6. A method, comprising:
 extracting, by a column driver that drives a column of pixels of a display device, a refresh status from a second field of a first data packet sent by a controller of the display device; 
 determining, by the column driver, that the refresh status indicates that a first pixel of the column of pixels is to be refreshed during an image refresh operation; and 
 transmitting, by the column driver, pixel data contained in a first field of the first data packet to the first pixel of the column of pixels in response to the determining that the refresh status indicates that a first pixel of the column of pixels is to be refreshed. 
 
     
     
       7. The method of  claim 6 , wherein the display device is a head mounted display. 
     
     
       8. The method of  claim 6 , wherein the first pixel resides at an intersection of the column of pixels and a row of pixels, and wherein the refresh status causes the first pixel to be refreshed at a different refresh rate than other pixels residing in the row of pixels. 
     
     
       9. The method of  claim 6 , further comprising:
 extracting, by the column driver, a refresh status from a second field of a second data packet sent by the controller of the display device; 
 determining, by the column driver, that the refresh status from the second field of the second data packet indicates that a second pixel of the column of pixels is not to be refreshed during the image refresh operation; and 
 preventing transmission, by the column driver, of pixel data to the second pixel of the column of pixels in response to determining that the refresh status from the second field of the second data packet indicates that the second pixel is not to be refreshed. 
 
     
     
       10. The method of  claim 9 , wherein the second pixel is located in a region of the display device that is on a periphery of a viewer's gaze. 
     
     
       11. The method of  claim 10 , wherein a fidelity of an image displayed on the display device is lower in the region relative to other regions of the display device. 
     
     
       12. The method of  claim 6 , wherein the second field of the first data packet contains a yes/no indicator to indicate the refresh status. 
     
     
       13. The method of  claim 6 , wherein the second field of the first data packet contains a 1/0 indicator to indicate the refresh status, where 1 indicates that the first pixel should be refreshed, and 0 indicates that the first pixel should not be refreshed. 
     
     
       14. The method of  claim 6 , wherein at least one selected from: the first field of the first data packet and the second field of the first data packet is contained in a payload of the first data packet. 
     
     
       15. The method of  claim 6 , wherein at least one selected from: the first field of the first data packet and the second field of the first data packet is contained in a header or footer of the first data packet. 
     
     
       16. A non-transitory machine-readable storage medium encoded with instructions executable by a processor, the machine-readable storage medium comprising:
 instructions to extract a refresh status from a second field of a first data packet sent by a controller of a display device; 
 instructions to determine that the refresh status indicates that a first pixel of a column of pixels is to be refreshed during an image refresh operation; and 
 instructions to transmit pixel data contained in a first field of the first data packet to the first pixel in response to a determination that the refresh status indicates that the first pixel is to be refreshed during an image refresh operation. 
 
     
     
       17. The non-transitory machine-readable storage medium of  claim 16 , wherein the display device is a head mounted display. 
     
     
       18. The non-transitory machine-readable storage medium of  claim 16 , wherein the first pixel is located in a region of the display device toward which a viewer's gaze is directed. 
     
     
       19. The non-transitory machine-readable storage medium of  claim 18 , wherein a fidelity of an image displayed on the display device is greater in the region relative to other regions of the display device which are on a periphery of the viewer's gaze. 
     
     
       20. The non-transitory machine-readable storage medium of  claim 16 , wherein the first pixel resides at an intersection of the column of pixels and a row of pixels, and wherein the refresh status causes the first pixel to be refreshed at a different refresh rate than other pixels residing in the row of pixels.